SPERMATOPHORES AND SPERMATOZOA OF THE SQUID LOLIGO PEALII.

Abstract

In the squid, spermatozoa are encased in spermatophores formed from male accessory secretions. Spermatophores about 1 cm in length were found to contain between seven and ten million densely packed spermatozoa. The substance of the sphermatophore itself was identified chiefly as a protein-polysaccharide complex, the precise composition differing among the various tunics and membranes; outer layers were classed as mucopolysaccharides, and the inner as mucoproteins. Of special morphological interest is the spiral filament consisting of tightly packed stellate particles in a gelatinous matrix, and of chemical interest the ‘cement’ which appears to be a strongly alkaline substance. A photomicrographic record was made of the spermatophoric reaction, which results in the release of the spermatozoa. Metabolic studies carried out with suspensions of squid spermatozoa have shown that the motility of such spermatozoa can be extended significantly by the addition of glycolys-able sugars. The ability of squid spermatozoa to convert glucose and fructose into lactic acid contrasts markedly with the lack of glycolytic ability which characterizes the spermatozoa of invertebrates with fully external fertilization. The spermatophore fluid of the squid contains a substance which, when added to a suspension of washed spermatozoa, causes a distinct inhibition of sperm motility and respiration; the nature of the factor responsible for this effect is still unknown.